The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 26, 1991
Filed:
Sep. 14, 1990
Applicant:
Inventors:
Norman M Pavlik, Wilkinsburg, PA (US);
John Sefko, Monroeville, PA (US);
Richard A Miller, N. Huntingdon, PA (US);
Assignee:
ABB Power T & D Company, Inc., Blue Bell, PA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01F / ;
U.S. Cl.
CPC ...
148307 ; 148308 ; 428596 ; 428611 ; 428638 ; 428928 ;
Abstract
A steel sheet (10) having a stress-relief annealed, structure with a plurality of magnetic domains (12) is made by drilling a plurality of closely spaced, small holes (15) through the entire thickness of the steel sheet, where the drilling is effective to form additional domain walls (17) and subdivide the magnetic domains.